PURPOSE: A structure of a portable catalytic combustion method gas sensor is provided to accurately operate without errors as a reference value of a compensation unit is not changed by preventing heat generated in a sensing unit from being transferred to the compensation unit. CONSTITUTION: A structure of a portable catalytic combustion method gas sensor comprises a sensing unit element(11) and a compensation unit element(21). The sensing unit element is heated at a temperature of higher than 300°C when a voltage is applied while in the state of being exposed to combustible gas and oxygen. The compensation unit element maintains a regular temperature regardless of the existence of the combustible gas and oxygen. The sensing unit element is connected to a pair of sensing poles(12) which faces each other so that a sensing unit(10) is formed. The compensation unit element is connected to a pair of compensation poles(22) which faces each other so that a compensation unit(20) is formed.